#include <bits/stdc++.h>
#define _rep(i, x, y) for(int i = x; i <= y; ++i)
#define _req(i, x, y) for(int i = x; i >= y; --i)
#define _rev(i, u) for(int i = head[u]; i; i = e[i].nxt)
#define pb push_back
#define fi first
#define se second
#define mst(f, i) memset(f, i, sizeof f)
using namespace std;
#ifdef ONLINE_JUDGE
#define debug(...) 0
#else
#define debug(...) fprintf(stderr, __VA_ARGS__), fflush(stderr)
#endif
typedef long long ll;
typedef pair<int, int> PII;
namespace fastio{
    #ifdef ONLINE_JUDGE
    char ibuf[1 << 20],*p1 = ibuf, *p2 = ibuf;
    #define get() p1 == p2 && (p2 = (p1 = ibuf) + fread(ibuf, 1, 1 << 20, stdin), p1 == p2) ? EOF : *p1++
    #else
    #define get() getchar()
    #endif
    template<typename T> inline void read(T &t){
        T x = 0, f = 1;
        char c = getchar();
        while(!isdigit(c)){
            if(c == '-') f = -f;
            c = getchar();
        }
        while(isdigit(c)) x = x * 10 + c - '0', c = getchar();
        t = x * f;
    }
    template<typename T, typename ... Args> inline void read(T &t, Args&... args){
        read(t);
        read(args...);
    }
    template<typename T> void write(T t){
        if(t < 0) putchar('-'), t = -t;
        if(t >= 10) write(t / 10);
        putchar(t % 10 + '0');
    }
    template<typename T, typename ... Args> void write(T t, Args... args){
        write(t), putchar(' '), write(args...);
    }
    template<typename T> void writeln(T t){
        write(t);
        puts("");
    }
    template<typename T> void writes(T t){
        write(t), putchar(' ');
    }
    #undef get
};
using namespace fastio;
#define multitest() int T; read(T); _rep(tCase, 1, T)
namespace Calculation{
    const ll mod = 998244353;
    ll ksm(ll p, ll h){ll base = p % mod, res = 1; while(h){if(h & 1ll) res = res * base % mod; base = base * base % mod, h >>= 1ll;} return res;}
    void dec(ll &x, ll y){x = ((x - y) % mod + mod) % mod;}
    void add(ll &x, ll y){x = (x + y) % mod;}
    void mul(ll &x, ll y){x = x * y % mod;}
    ll sub(ll x, ll y){return ((x - y) % mod + mod) % mod;}
    ll pls(ll x, ll y){return ((x + y) % mod + mod) % mod;}
    ll mult(ll x, ll y){return x * y % mod;}
}
using namespace Calculation;
const int N = 4e5 + 5;
typedef long double lb;
int q, w;
map<PII, bool> vis;
PII a[N];
int len, lsh[N];
namespace sgt{
    int minx[N << 2], cnt[N << 2], tag[N << 2];
    #define ls x << 1
    #define rs x << 1 | 1
    void update(int x){
        minx[x] = min(minx[ls], minx[rs]);
        cnt[x] = (minx[ls] == minx[x]) * cnt[ls] + (minx[rs] == minx[x]) * cnt[rs];
    }
    void pushtag(int x, int val){minx[x] += val, tag[x] += val;}
    void pushdown(int x){
        if(!tag[x]) return;
        pushtag(ls, tag[x]), pushtag(rs, tag[x]), tag[x] = 0;
    }
    void modify(int x, int l, int r, int L, int R, int val){
        if(l >= L && r <= R) return pushtag(x, val);
        pushdown(x);
        int mid = l + r >> 1;
        if(L <= mid) modify(ls, l, mid, L, R, val);
        if(R > mid) modify(rs, mid + 1, r, L, R, val);
        update(x);
    }
    void build(int x, int l, int r){
        if(l == r) return minx[x] = 0, cnt[x] = lsh[l + 1] - lsh[l], void();
        int mid = l + r >> 1;
        build(ls, l, mid), build(rs, mid + 1, r);
        update(x);
    }
    int solve(){
        int cur = !minx[1] ? cnt[1] : 0;
        return cur;
    }
}
using namespace sgt;
void ins(int x, int y){
    int tl = max(0, x - y), tr = min(w, x + y);
    tl = lower_bound(lsh + 1, lsh + 1 + len, tl) - lsh, tr = lower_bound(lsh + 1, lsh + 1 + len, tr) - lsh;
    if(tl < tr) modify(1, 1, len - 1, tl, tr - 1, 1); 
}
void del(int x, int y){
    int tl = max(0, x - y), tr = min(w, x + y);
    tl = lower_bound(lsh + 1, lsh + 1 + len, tl) - lsh, tr = lower_bound(lsh + 1, lsh + 1 + len, tr) - lsh;
    if(tl < tr) modify(1, 1, len - 1, tl, tr - 1, -1);
}
int main(){
    read(q, w);
    _rep(i, 1, q){
        read(a[i].fi, a[i].se);
        if(a[i].fi - a[i].se > 0)
            lsh[++len] = a[i].fi - a[i].se;
        if(a[i].fi + a[i].se <= w)    
            lsh[++len] = a[i].fi + a[i].se;
    }
    lsh[++len] = 0, lsh[++len] = w;
    sort(lsh + 1, lsh + 1 + len), len = unique(lsh + 1, lsh + 1 + len) - lsh - 1;
    build(1, 1, len - 1);
    _rep(i, 1, q){
        int x = a[i].fi, y = a[i].se;        
        if(vis[{x, y}]) del(x, y), vis[{x, y}] = 0;
        else ins(x, y), vis[{x, y}] = 1;
        int cur = w - solve();
        lb res = (lb)cur * sqrtl(2.00);
        printf("%.10Lf\n", res);
    } 
    return 0;
}